Chip card reader having contact and contactless operating modes

1. A chip card reader comprising: a central processing unit comprising means for emitting and receiving, on a communication bus having a single data wire, binary messages having a first format determined by a communication protocol for contact chip cards, a card receiving device comprising a contact card connector connected to the central processing unit by means of the communication bus, the contact card connector being therefore connected to said single data wire, and a contactless read head for contactless chip card comprising: means for receiving or sending, from or to a contactless chip can, messages having a second format determined by a communication protocol for contactless chip cards, a serial interface directly connected to said single data wire of said communication bus that carries the binary messages having the first format determined by a communication protocol for contact chip cards, means for converting messages received on the serial interface and having the first format into messages having the second format, and, vice versa, converting messages received from a contactless chip card and having the second format into messages having the first format applied on the serial interface, and hardware and software arranged so that the contactless read head does not respond to a contact chip card activation command received on the serial interface, and responds to a specific activation command of the contactless read head different from a contact chip card activation command.

2. The reader according to claim 1 , wherein the contactless read head is further electrically supplied by a supply wire of the communication bus.

3. The reader according to claim 1 , wherein the contactless read head comprises means for being set into an inhibition state at its power-on, and for leaving the inhibition state when receiving said specific activation command.

4. The reader according to claim 3 , wherein the central processing unit comprises means for performing the following operations when receiving a detection signal of the presence of a card in the reader: sending, on the communication bus, a contact card activation command, and waiting for a first response; if the first response is received, establishing or trying to establish a communication with a contact card, if the first response is not received in a predetermined time interval, sending said specific activation command of the contactless read head on the communication bus, and waiting for a second response, if the second response is received, establishing or trying to establish a communication with a contactless curd.

5. The reader according to claim 4 , wherein said contact card activation command is a reset command according to the standard ISO 7816.

6. The reader according to claim 1 , wherein said specific activation command of the read head is a command which is likely to be never sent to a contact chip card.

7. The reader according to claim 1 , in which the contactless read head is integrated in a small size circuit arranged close to or inside the card-receiving device.